The present invention relates to lubrication systems, in particular automatic lubrication systems for lubricating machine components
Lubrication systems are known and typically contain a reservoir containing lubricant, one or more fluid supply lines for transporting the lubricant to a location to be lubricated, such as a machine component (e.g., a bearing) and a pump or other means to initiate flow from the reservoir, through the fluid lines and to the component to be lubricated. In certain systems, a valve controls flow from the supply line to the machine component and a controller is provided to operate the pump and open the valve(s). Typically, the controller will start the pump at a set time interval, open the one or more valves and then close the valves and stop the pump when all machine components have received re-lubrication.
However, with lubrication systems for lubricating numerous separate machine components that are spaced a substantial distance apart, the lubricant may be disposed within or reside in the supply line for a substantial period of time. Particularly when the lubricant is grease, the lubricant may break-down and become ineffective after residing in the supply line for a prolonged period, which could lead to failure of machine components if the lubricant is dispensed thereon. More specifically, the grease will degrade over time and become ineffective to prevent metal-to-metal contact between the lubricated components, as grease tends to lose consistency, such that oil in the grease bleeds out, and/or oxidizes and breaks down, so as to be generally incapable of providing a film thickness. Such degradation increases at elevated temperatures and higher speeds of the lubricated components, so as to decrease the effective “life” of the grease.